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What is blood glucose monitoring?

Blood glucose levels (also called blood sugar levels) reflect how well diabetes is being controlled and how well the plan of care (diet, exercise, and medication) is working.  If the blood sugar levels are consistently under control (with levels near normal), diabetes complications may be reduced or even prevented.

How can blood sugar levels be checked?

In proper diabetes management, checking blood glucose levels regularly is very important with current methods of blood sugar monitoring requiring a blood sample.  Monitoring blood sugar can be done at home with a variety of invasive devices to obtain the blood sample (invasive means the penetrations of body tissue with a medical instrument).

A drop of blood is obtained through a finger prick to use on a test strip that is then measured in a monitor.  A finger prick can be done with a small lancet (special needle) or with a spring-loaded lancet device that punctures the fingertip quickly.  The strip goes into the meter first, that a drop of blood is placed on the tip of the strip that reads the blood sugar level.

Today, there are many types of monitors on the market, ranging in price, ease of use, size, portability, and length of testing time.  Each monitor requires its own type of testing strip.  If correctly used, blood glucose monitors have been found to be accurate and reliable, and most monitors provide results within seconds.  For visually or physically impaired, there are monitors that give verbal testing instructions and verbal test results.  There are glucose monitors available that provide verbal instructions in Spanish and other languages as well.

People with diabetes may have to check their blood sugar levels up to 4 times a day.  Blood sugar levels can be affected by several factors, including the following:

  • Diet
  • Diabetes medication
  • Exercise
  • Stress
  • Illness 

Certain blood glucose monitors are equipped with data-management systems, which means your blood glucose measurement is automatically stored each time.  Some physician offices have computer systems compatible with these data-management systems, which allows the blood sugar level recordings, and other information, to be transferred electronically.  This can be done on your home computer as well.  One advantage of a data management system is the ability to plot a graph on the computer depicting patterns of blood sugar levels.  

What are healthy blood sugar level ranges?

Blood sugar levels over 200 mg/dl (mg/dl=milligrams of glucose per deciliter of blood) or under 70 mg/dl are considered unhealthy.  High blood sugar levels that are about 200 mg /dl may be a sign of inadequate levels of insulin, caused by overeating, lack of exercise, or other factors.  Low blood sugar levels that are below 70 mg/dl may be caused by taking too much insulin, skipping or postponing a meal, over-exercising, excessive alcohol consumption, or other factors.  A good range for most people is between 70 and 130 mg/dl.   

Most common symptoms of hyperglycemia (high blood sugar) include :

  • Rapid, unexplained weight loss
  • Feeling sick
  • Intense thirst
  • Increased urination
  • Vomiting
  • Fatigue
  • Blurred vision
  • Fainting

​​​ *Each individual may experience symptoms differently or no symptoms at all.

Most common symptom of hypoglycemia (low blood sugar) include:

  • Hunger
  • Fatigue
  • Shakiness
  • Headaches
  • Confusion
  • Dizziness
  • Sudden moodiness or behavior changes
  • Sweating
  • Pale skin color

Sometimes, none of these warning symptoms appear before a person loses consciousness from low blood glucose; the loss of consciousness is called hypoglycemia unawareness.

*Each individual may experience symptoms differently or no symptoms at all.